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Urban forestry professionals are increasingly challenged to find cost-effective strategies for resource conservation and management. Many organizations partner with citizen groups to host events that enlist volunteers to perform stewardship tasks like tree planting and trail maintenance. These volunteer programs incur costs to both the managing agency and partners, such as staffing, tools, and transportation. Volunteers contribute uncompensated time and expertise. Little is known about these contributions, yet citizen stewards and host groups represent an important human dimension of urban forest management. Using a survey administered to volunteers and host organizations at restoration events in King County Parks, WA, USA, we developed a cost-based approach to estimate the value of stewardship activities that occurred in the spring field season of 2011. Expenditures included volunteer and event host time and direct cost of traveling to and from events, on-site labor, equipment, and preparation costs. Results suggest that contributions made by volunteers and hosts are significant; the combined costs associated with the 17 sampled events was approximately $35,700. These efforts represent a small subset of the more than 1000 volunteer environmental stewardship activities that take place annually in King County.  相似文献   
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BackgroundAcute phase proteins (APP) may guide treatment of pneumonia in dogs but correlations with radiographic abnormalities are poorly characterized.ObjectivesDevelop a thoracic radiographic severity scoring system (TRSS), assess correlation of radiographic changes with APP concentrations, and compare time to APP and radiograph normalization with duration of antimicrobials treatment.AnimalsSixteen client‐owned dogs, 12 with aspiration pneumonia, and 4 with community‐acquired pneumonia.MethodsConcentrations of C‐reactive protein (CRP), serum amyloid A (SAA), and haptoglobin were measured on days 1, 3, 7, 14, 28, and 60 and orthogonal 2‐view thoracic radiographs were obtained on days 1, 7, 14, 28, and 60. Treatment was clinician‐guided and blinded to APP concentrations. Radiographic severity scores were assigned by blinded, randomized retrospective review by 2 board‐certified radiologists with arbitration by a third radiologist.ResultsMedian (interquartile range [IQR]) time to normalization of CRP (7 days [7‐14]) and SAA concentrations (7 days [7‐14]) were shorter than antimicrobial treatment duration (17.5 days [14.5‐33.5]; P = .001 and .002, respectively) and TRSS normalization (14 days [8.8‐52], P = .02 and .02, respectively). The CRP and SAA concentrations were positively correlated with TRSS (CRP r s , 0.643; SAA r s , 0.634; both P < .0001). Both CRP and SAA identified normal thoracic radiographs area under the curve (AUC) 0.873 and 0.817, respectively, both P < .0001. Interobserver agreement for TRSS assignment was moderate (κ, .499; P < .0001).Conclusion and Clinical ImportanceConcentrations of CRP and SAA normalized before radiographic resolution and before clinicians discontinued antimicrobial treatment. The CRP and SAA concentrations may guide duration of antimicrobial treatment for dogs with pneumonia.  相似文献   
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A dog was presented with signs of subacute, progressive myelopathy. A tentative diagnosis of a diffuse intramedullary spinal cord mass was made using contrast radiography (myelography). At autopsy a solitary, large bronchoalveolar carcinoma was detected in a lung lobe. Histological examination of the cranial thoracic spinal cord revealed a tumour which was similar, but not identical, to the lung tumour. Immunohistochemistry helped to confirm that the spinal lesion was a metastasis of the lung tumour.  相似文献   
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One grazing and two feeding experiments were conducted to compare the feeding value of corn residue or corn grain from a genetically enhanced corn hybrid (corn rootworm-protected; event MON 863) with nontransgenic, commercially available, reference hybrids. In Exp. 1, two 13.7-ha fields, containing corn residues from either a genetically enhanced corn root-worm-protected hybrid (MON 863), or a near-isogenic, nontransgenic control hybrid (CON) were divided into four equal-sized paddocks. Sixty-four steer calves (262 +/- 15 kg) were stratified by BW and assigned randomly to paddock to achieve a stocking rate of 0.43 ha/steer for 60 d, with eight steers per paddock and 32 steers per hybrid. A protein supplement was fed at 0.45 kg/steer daily (DM basis) to ensure protein intake did not limit performance. Steer ADG did not differ (P = 0.30) between steers grazing the MON 863 (0.39 kg/d) and CON (0.34 kg/d) corn residues for 60 d. The four treatments for the feeding experiments (Exp. 2 and 3) included two separate reference hybrids, the near-isogenic control hybrid (CON), and the genetically enhanced hybrid (MON 863) resulting in two preplanned comparisons of CON vs. MON 863, and MON 863 vs. the average of the reference hybrids (REF). In Exp. 2, 200 crossbred yearling steers (365 +/- 19 kg) were fed in 20 pens, with five pens per corn hybrid. In Exp. 3, 196 crossbred yearling steers (457 +/- 33 kg) were fed in 28 pens, with seven pens per corn hybrid. In Exp. 2, DMI and G:F did not differ (P > 0.10) between MON 863 and CON; however, steers fed MON 863 had a greater (P = 0.04) ADG than steers fed CON. Gain efficiency was greater (P = 0.05) for MON 863 cattle than for REF cattle in Exp. 2, but other performance measurements (DMI and ADG) did not differ (P > 0.10) between MON 863 and REF. No differences (P > 0.10) were observed for performance (DMI, ADG, and G:F) between MON 863 and CON or MON 863 and REF in Exp. 3. In terms of carcass characteristics, no differences (P > 0.10) were observed between MON 863 and CON, as well as MON 863 and REF, for marbling score, LM area, or 12th rib fat thickness in both Exp. 2 and 3. Overall, performance was not negatively affected in the corn residue grazing or feedlot experiments, suggesting the corn rootworm-protected hybrid (event MON 863) is similar to conventional, nontransgenic corn grain and residues when utilized by beef cattle.  相似文献   
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Koalas (Phascolarctos cinereus) are experiencing significant declines across the northern part of their range. However, unbiased, population‐level estimates of mortality are rarely reported, as it's difficult to quantify causes of mortality robustly in this cryptic species. We aimed to determine the relative importance of carpet python (Morelia spilota) predation in a free‐living koala population and describe the characteristic pathological findings during necropsy. In total, 503 koalas were captured, underwent veterinary examination and telemetric tagging, and were monitored after release over a four‐year period. Mortalities were detected when activity data reported by K‐Tracker® biotelemetry collars indicated low or zero activity, or during routine field monitoring events. Experienced koala veterinarians performed thorough, standardised necropsy examinations on retrieved carcasses to determine causes of death. The three, sometimes subtle, cardinal signs used to definitively diagnose carpet python‐caused deaths of koalas were a U‐shaped primary bite site, slicking of the fur by python saliva (particularly around the face), and diffuse, uniform pulmonary congestion. We found that carpet pythons were important predators of koalas, second only to wild dogs (dingoes and dingo hybrids (Canis familiaris dingo)), accounting for 11.6% of predation deaths and 7.2% of total deaths. Less than half (38%) of the koalas killed by carpet pythons were ingested. Though carpet pythons are known predators of koalas, their relative importance as a cause of mortality hasn't previously been recognised. Population viability analyses and conservation management plans benefit from robust cause‐of‐death data collected during longitudinal monitoring studies, requiring telemetry methods that facilitate rapid detection of mortalities.  相似文献   
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A new chromatographic approach for separating cacao procyanidins according to their degree of polymerization has been developed. It utilizes diol stationary phase columns operating in normal phase mode with a binary gradient of acidified acetonitrile and methanol-water. Performance of the diol stationary phase was evaluated on an analytical scale utilizing classical chromatographic conditions for the normal phase separation of procyanidins according to their degree of polymerization. The new separation approach was developed on an analytical scale but further extended to the preparative scale. These newly developed analytical and preparative high-performance liquid chromatography procedures were successfully applied to the separation, as well as isolation, of cacao procyanidins from unfermented cacao seeds. The degree of polymerization associated with each molecular weight fraction was determined by mass spectrometry.  相似文献   
60.
New Evidence from Biogenic Silica in Sediments New evidence from studies of biogenic silica and diatoms in sediment cores indicates that eutrophication in the lower Great Lakes resulted from nutrient enrichment associated with early settlement and forest clearance. Diatom production peaked from 1820 to 1850 in Lake Ontario, at about 1880 in Lake Erie, but not until 1970 in Lake Michigan. This is the first reported sediment record of the silica-depletion sequence for the Great Lakes.  相似文献   
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